Recently, large-capacity magnetoresistive random access memories (MRAM) using a magnetic tunnel junction (MTJ) element have been gaining attention and raising expectations. The MTJ element comprises the following two magnetic layers sandwiching a tunnel barrier layer: a magnetization fixed layer (reference layer) having a fixed direction of magnetization and a magnetization free layer (storage layer) having an easily reversible direction of magnetization. There is a case in which the MTJ element further comprises a shift-adjustment layer to prevent the influence of a stray magnetic field.
When the shift-adjustment layer of the MTJ element is made thick, variations in the in-plane grain size occur, which leads to variations in the perpendicular magnetic anisotropy of an element as formed. In the case of the shift-adjustment layer having a multilayer artificial lattice in particular, since the grains grow as the thickness of the layer increases, the variations become wider.